team for AUG

Who I can recommend mostly depends on who you have available to fill the spots. It's difficult to recommend characters you don't have when rng may keep them away from you for months. (I still don't have g41 for example and I've been playing for about 8 months >.>)

The one thing I can say though is you're probably going to overstack crit with both 45 and shremp in the same echelon. If you really want 45 as the MT then maybe swap shremp out for vector (skorpion or pps-43 works too if you don't have access to vector).

Ideally going off full access to any t-doll probably something like ...
G36|Z62
AUG|UMP45
M21

Z62 is probably the most difficult one from that group since she was a limited reward from operation cube. But she's easily replaced with PPS-43 who is fairly easy to acquire. Other than that there's G36 who is also pretty rare but what you're looking for mainly is a damage buff to your off-tank so G11 will work just as well if you have her. (Though after MOD3 G36 will outstrip any other off-tank buffer by a large margin)

As for why I recommend that specific group is based around AUG's ability. When she activates it she will absolutely melt an enemy backline IF she can ignore the frontline. The combination of Zas's grenade and an offtank's grenade can fairly reliably make that a non-issue by simply removing the majority of the frontline with very fast initial cooldown grenades.

I do personally use a slightly different group for AUG but that's mainly because I play with a personal "no duplicates" rule for my echelons.

Aside from my recommendation though AUG does work in a lot of echelons due to the combined nature of her Formation buff and her powerful personal skill. It's just down to avoiding buff redundancy in stats with hard caps like crit and RoF.